Fiber transporting device

ABSTRACT

The doffer of this invention includes a rotatable cylindrical structure with a plurality of solid doffing blades (equal in width to the apron width) extending outwardly and backwardly (with respect to the direction of doffer rotation) from the cylinder circumference at an incline (5 to 60*) with respect to a radially directed reference line. The entire cylinder and doffer blade assembly is painted with a synthetic resin paint or otherwise treated to insure a substantially smooth outer surface. (A finish of 32 or smoother on a standard finish scale is sufficient.) In operation, this cylindrical doffer is preferably mounted for rotation such that the blades pass by the apron in the same direction as the moving apron pins but without any intermeshing therebetween. (A clearance of approximately 1/4 inch is provided.) As the doffer is rotated at fairly high speeds, a doffing sheet of moving air is generated over the entire width of the apron to remove fibers therefrom (i.e. fanning action). In addition, because of the extreme smoothness of the outer doffer surfaces, stray fibers are in no way caught up in the doffer itself to accumulate and interfere with the desired doffing operation.

United States Patent Lytton et al.

[ Oct. 24, 1972 [54] FIBER TRANSPORTING DEVICE [72] Inventors: Kenneth G. Lytton; David F. Hullett; George J. Miller, all of Gastonia, NC.

[73] Assignee: Fiber Controls Corporation,

Gastonia, NC.

[22] Filed: Jan. 29, 1971 [21] Appl. No.: 111,013

[52] U.S. Cl ..l98/103, 198/211 [51] Int. Cl. ..B65g 29/00, B65g 37/00 [58] Field of Search ..l9/105, 106; 198/103, 167, 198/211 [56] References Cited UNITED STATES PATENTS 1,200,775 10/1916 Stevenson ..198/167 X 346,418 7/1886 Tromblay ..19/105 2,600,969 6/1952 Clapperton ..19/ 105 FOREIGN PATENTS OR APPLICATIONS 634,929 3/1950 Great Britain ..l9/l05 Primary Examiner-Edward A. Sroka Attorney-Cushman, Darby & Cushman [57] ABSTRACT The doffer of this invention includes a rotatable cylindrical structure with a plurality of solid doffing blades (equal in width to the apron width) extending outwardly and backwardly (with respect to the direction of doffer rotation) from the cylinder circumference at an incline (5 to 60) with respect to a radially directed reference line. The entire cylinder and doffer blade assembly is painted with a synthetic resin paint or otherwise treated to insure a substantially smooth outer surface. (A finish of 32 or smoother on a standard finish scale is sufficient.)

In operation, this cylindrical doffer is preferably mounted for rotation such that the blades pass by the apron in the same direction as the moving apron pins but without any intermeshing therebetween. (A clearance of approximately inch is provided.) As the doffer is rotated at fairly high speeds, a doffing sheet of moving air is generated over the entire width of the apron to remove fibers therefrom (i.e. fanning action). In addition, because of the extreme smoothness of the outer doffer surfaces, stray fibers are in no way caught up in the doffer itself to accumulate and interfere with the desired doffing operation.

8 Claims, 3 Drawing Figures FIBER TRANSPORTING DEVICE BACKGROUND OF THE INVENTION The invention is in the field of doffers of the type which are employed near the upper rear side of an inclined fiber lift apron in any fiber feeding hopper or the like. A conventional doffer of the oscillating type or of the revolving type, employs pins at various places along the circumference and length of the doffer, to doff or strip the fibers from the apron pins as they bring the fibers over the upper reach of the lift apron. Generally, the doffer pins and apron pins intermesh. The blades of the presently preferred embodiment of the doffer of the present invention extend the full length of the doffer and do not intermesh with the apron pins; there is some clearance therebetween, such as A inch.

The doffer came about after many years of seeking a solution to the problem of long staples (3 inches or longer). One possible solution worked on was the use of a blower of the type disclosed in U.S. Pat. No. 3,322,331 to blow the fibers from the apron of a card feeder, but that blower, though having other usefulness in the art, was not satisfactory for this particular use.

The problem is that long staples tend to wrap around the doffer or catch on the doffing pins and fail to be thrown off of the doffer (though removed from the apron) into the collector, e.g. a weigh pan or chute under the doffer. While an oscillating doffer of the Sargeant comb type as in U.S. Pat. No. 3,355,773, for example, seems to overcome the problem, it can generate another problem, that of causing too much vibration and consequent mechanical shock and repair problems because it must cover a 110 arc and move back and forth at quite high speeds (more so in the way of arc and speed than a combing operation in front of the lift apron).

The following additional United States patents are acknowledged as being in the body or prior art pertinent to the present invention:

1,222,733 Calderwood (1917) 2,748,998 Busald (I956) 2,985,921 Worley (I961) The Calderwood patent generally shows a combination fan and doffer 7 which is used to remove fibers from a drum 6 onto a horizontal belt 8 without physically engaging the drum or fibers while, at the same time, blowing away unwanted dirt in a cleaning action. While the patent is somewhat vague as to the exact structure of this fan-doffer, possible the blades are solid and extend across substantially the entire width of the cylindrical structure. It is significant, however, to note that the blades are apparently not inclined with respect to a radial line nor is any effort made to keep the entire outer surface within any limits of smoothness.

The Busald patent is a later device which utilizes a doffer shown in FIG. 3. Here the doffer 31 has a cylindrical body and four outwardly extending flexible arms which are inclined backwardly with respect to a radial line. However, it should be noted that the outer edges of Busalds flexible blades 34 apparently do physically engage the apron pins 17 as shown by the dotted lines in FIG. 3. This being so, the Busald doffer is believed to turn at a relatively slow speed which does not, therefore, produce a fanning action. Further, there is no mention in Busald of keeping the outer doffer surfaces smooth and in fact, the actual figures of the Busald patent show many sharp edges and corners.

Finally, the Worley patent is cited to definitely show the use of a stripper or doffer comprising solid blades extending across substantially the entire width of a cylindrical stripper element. Here, as in Busald, the blades are flexible, and no fanning action is apparently utilized but rather a physical stripping action is relied upon. The Worley reference also fails to teach a smooth outer doffing surface.

SUMMARY OF THE INVENTION In its preferred form, the present invention provides a solution to the catching and wrapping problem discussed in the foregoing section in the form of a full length, round doffer, with several (e.g. four) full length blades which slope backwards in the area of 5 to preferably 12, from a radial line, to effect a fan-type doffing operation. Also significant is the fact that the doffer blades and surface of the drum must be quite smooth. At the present time it is believed that the finish thereof must be 32 or less on a standard finish scale (for example, 324T on commercially available basic surface roughness specimen scale; part number PAG 490 of Ash Precision, 650 East Mandoline, Madison Heights, Michigan). Such a finish might be obtained in different ways, but definitely can be successfully obtained in different ways, but definitely can be successfully obtained by painting the doffer (blades and drum) with a Sherwin-Williams synthetic resin paint presently sold under the Trademark Polane, which is a crossbonded rubber and polyurethane. An alternative smoothener for the doffer is chemical deburring, provided the required smoothness is obtained throughout.

The doffer of this invention includes a rotatable cylindrical structure with a plurality of solid doffing blades (equal in width to the apron width) extending outwardly and backwardly (with respect to the direction of doffer rotation) from the cylinder circumference at an incline (5 to 60) with respect to a radially directed reference line. The entire cylinder and doffer blade assembly is painted with a synthetic resin paint or otherwise treated to insure a substantially smooth outer surface. (A finish of 32 or smoother on a standard finish scale is sufficient.)

In operation, this cylindrical doffer is preferably mounted for rotation such that the blades pass by the apron in the same direction as the moving apron pins but without any intermeshing therebetween. (A clearance of approximately M1 inch is provided.) As the doffer is rotated at fairly high speeds, a doffing sheet of moving air is generated over the entire width of the apron to remove fibers therefrom (i.e. fanning action). In addition, because of the extreme smoothness of the outer doffer surfaces, stray fibers are in no way caught up in the doffer itself to accumulate and interfere with the desired doffing operation. I

The principles of the invention will be further hereinafter discussed with reference to the drawing wherein a preferred embodiment is shown. The specifics illustrated in the drawing are intended to exemplify, rather than limit, aspects of the invention as defined in the claims.

BRIEF DESCRIPTION OF THE DRAWING In the drawing, FIG. 1 is an appropriately captioned illustration of the doffer of the invention in preferred jextaposition with an apron. (FIG. of US. Pat. No. 3,196,967 granted July 27, 1965, to one of the present inventors shows a typical context of a doffer and apron combination.

FIG. 2 is an end elevation view of a presently preferred embodiment of the doffer illustrated'schematically in FIG. 1; and

FIG. 3 is a side elevation view of the doffer embodiment of FIG. 2.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENT In the drawing there is shown an apron in the form of a wide endless belt having apron pins 12 which project outwardly and forwardly therefrom to lead the travel of the apron as it runs out the upper and lower rolls l4, l6. Beside the upper end of the apron, a doffer l8 constructed in accordance with the principles of the present invention is mounted for rotation.

The rotation axis of the roll 14 is parallel to the rotation axis of the doffer 18.

The doffer 18 includes a hollow cylindrical roll 20 with a plurality of equiangularly spaced bars (blades, paddles) 22, four are shown, projecting e. g. 2 inches up from the outer surface 24 of the cylinder. The radially outer ends of the bars trail the bases thereof by 5".60 and preferably by about 12.

In addition, the spacing and dimensioning of the apron and doffer are such that at their closest approach, the tips of the doffer bars 22 miss the tips of the apron pins 12 by about /1. inch.

The bars 22 are preferably substantially as wide as the apron 10. Typical over-all widths are 35.5 inches; 47.5 inches; 53.5 inches; 59.5 inches, and 71.5 inches. 16.125 inches is a typical over-all diameter of the doffer 18, including the bars thereon.

Preferably, the doffer is fabricated of steel plate of the kind used to fabricate conventional rotating doffers. Sharp angles, weld slag and crevices are preferably mechanically smoothed, and recesses and corners are filled with e. g. body putty.

Following this preparation, the entire fiber-contacting portions of the doffer, i.e. at least the outside of its cylinder and all of the bars, are smoothed to a surface roughness at least as smooth as 32 ST on the aforesaid roughness scale.

Although it is believed possible to produce the required smoothness using chemical deburring techniques, it is believed to be impractical under current industrial conditions in the textile machinery industry to achieve the required degree of over-all smoothness using purely mechanical smoothening techniques, such as steel wooling.

The presently preferred way of achieving the required smoothness is to paint the entire fiber-contacting portions of the doffer with a paint of the following composition:

Williams Sherwin- Williams The mixture is applied to the doffer, preferably by spraying (preferably in two coats) or dipping and cured in accordance with Sherwin-Williams label instructions to provide a continuous coating having a thickness of about at least 4-6 mils. The coating of cured synthetic resin is sufficiently tough as to last an acceptably long time and has a surface roughness which is no rougher than 32 ST on the Ash Precision Scale (when measured at randomly chosen unit squares of one square inch).

In operation, this cylindrical doffer is preferably mounted for rotation such that the blades pass by the apron in the same direction as the moving apron pins but without any intermeshing therebetween. (A clearance of approximately A. inch is provided). As the doffer is rotated at fairly high speeds, a doffing sheet of moving air is generated over the entire width of the apron to remove fibers therefrom (i.e. fanning action). In addition, because of the extreme smoothness of the outer doffer surfaces, stray fibers are in no way caught up in the doffer itself to accumulate and interfere with the desired doffing operation.

In the preferred coating, it is believed that the rubber imparts elasticity to the coating, needed to prevent chip-off and to give good wear characteristics and the urethane permits the coating to withstand chemical erosion due to chemicals often used to pretreat synthetic fibers, for instance, anti-static agents.

It should now be apparent that the doffer as described hereinabove possesses each of the attributes set forth in the specification under the heading Sum- ,mary of the Invention hereinbefore. Because the doffer of the invention can be modified to some extend without departing from the principles of the invention as they have been outlined and explained in this specification, the present invention should be understood as encompassing all such modifications as are within the spirit and scope of the following claims.

What is claimed is:

1. For doffing fibers from means transporting the fibers, a doffer including:

a roll having an outer cylindrical surface;

a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said transporting means;

all portions of the bars. and said surface exposed for contact with the fibers to be doffed being characterized by having a surface smoothness at least as smooth as 32 ST;

said portions possessing said smoothness by virtue of possessing an adherent coating of synthetic resin essentially consisting of rubber cross-linked with urethane.

' 2. The doffer of claim 1 wherein the bars angularly trail radians of the roll by 5.-60.

3. The doffer of claim 1 wherein the bars angularly trail redians of the roll by about 12.

4. For transporting fibers:

an endless apron entrained about two rotating rolls;

a plurality of apron pins projecting outwardly from the apron for transporting fibers; and a doffer including; a roll having an outer cylindrical surface;

a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said apron;

all portions of the bars and said surface exposed for contact with the fibers to be doffed being characterized by having a surface smoothness at least as smooth as 32 ST, possessing said smoothness by virtue of possessing an adherent coating of synthetic resin essentially consisting of rubber cross-linked with urethane;

there being a gap between the closest approach of the tips of the apron fingers to the doffer bars.

5. The apparatus of claim 4 wherein said gap measures at least about V4 inch.

6. The apparatus of claim 4 wherein the doffer bars trail radians of the doffer roll by 560.

7. For doffing fibers from means transporting the fibers, a doffer including:

a roll having an outer cylindrical surface;

a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said transporting means; all portions of the bars and said surface exposed for contact with the fibers to be doffed being characterized by having a surface smoothness at least as smooth as that obtainable by spray coating with synthetic resin essentially consisting of rubber cross-linked with urethane.

8. For doffing fibers from means transporting the fibers, a doffer including:

a roll having an outer cylindrical surface;

a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said transporting means;

all portions of the bars and said surface exposed for contact with the fibers to be doffed being characterized by having a continuous coating of smooth, adherent synthetic plastic resin. 

1. For doffing fibers from means transporting the fibers, a doffer including: a roll having an outer cylindrical surface; a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said transporting means; all portions of the bars and said surface exposed for contact with the fibers to be doffed being characterized by having a surface smoothness at least as smooth as 32 ST; said portions possessing said smoothness by virtue of possessing an adherent coating of synthetic resin essentially consisting of rubber cross-linked with urethane.
 2. The doffer of claim 1 wherein the bars angularly trail radians of the roll by 5*- 60*.
 3. The doffer of claim 1 wherein the bars angularly trail redians of the roll by about 12*.
 4. For transporting fibers: an endless apron entrained about two rotating rolls; a plurality of apron pins projecting outwardly from the apron for transporting fibers; and a doffer including; a roll having an outer cylindrical surface; a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said apron; all portions of the bars and said surface exposed for contact with the fibers to be doffed being characterized by having a surface smoothness at least as smooth as 32 ST, possessing said smoothness by virtue of possessing an adherent coating of synthetic resin essentially consisting of rubber cross-linked with urethane; there being a gap between the closest approach of the tips of the apron fingers to the doffer bars.
 5. The apparatus of claim 4 wherein said gap measures at least about 1/4 inch.
 6. The apparatus of claim 4 wherein the doffer bars trail radians of the doffer roll by 5*- 60*.
 7. For doFfing fibers from means transporting the fibers, a doffer including: a roll having an outer cylindrical surface; a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said transporting means; all portions of the bars and said surface exposed for contact with the fibers to be doffed being characterized by having a surface smoothness at least as smooth as that obtainable by spray coating with synthetic resin essentially consisting of rubber cross-linked with urethane.
 8. For doffing fibers from means transporting the fibers, a doffer including: a roll having an outer cylindrical surface; a plurality of bars projecting outwardly from said surface and extending along the width of the drum substantially the full width of said transporting means; all portions of the bars and said surface exposed for contact with the fibers to be doffed being characterized by having a continuous coating of smooth, adherent synthetic plastic resin. 